JP2022072934A - Navigation device, navigation method, and computer program - Google Patents

Abstract

To realize stable radio communication when remotely monitoring a moving body by radio communication.SOLUTION: A navigation device includes: a position radio quality base station information storage section that stores position radio quality base station information in which a position, radio communication quality, and base station identification information are associated; a cost calculation section that performs weighting on route candidates so that the route candidates are inferiorly evaluated if the radio communication quality is poor on the basis of the position radio quality base station information; a route search section that searches for a route from the weighted route candidates on the basis of the weighting; a radio quality old/new comparison section that compares the radio communication quality of the position radio quality base station information with radio communication quality at the timing when a moving body moves toward a destination; and a radio quality deterioration amount correction section that corrects a radio communication quality deterioration amount for the radio communication quality of the position radio quality base station information on the basis of a comparison result.SELECTED DRAWING: Figure 1

Description

The present invention relates to navigation devices, navigation methods and computer programs.

In recent years, navigation techniques assuming that autonomously moving robots and autonomous vehicles travel outdoors have been studied. For example, Patent Document 1 describes a navigation data generation system that acquires navigation data based on a navigation route and a node type of an intermediate node (an operation to be performed by a vehicle at a node) when automatically transporting an object. ing.

Special Table 2019-537730

When remotely monitoring a robot or an autonomous vehicle that moves autonomously outdoors by wireless communication, it is preferable to move on a route that does not disconnect the wireless communication. However, with the above-mentioned conventional navigation technique, it is not possible to navigate a route in which wireless communication is not disconnected.

The present invention has been made in consideration of such circumstances, and an object of the present invention is to realize stable wireless communication when remotely monitoring a mobile body by wireless communication.

(1) One aspect of the present invention is a navigation device that provides route information indicating a route from a departure point to a destination for a moving body in which remote monitoring is performed via a wireless communication line, and is a position and a position. Location wireless quality base station information storage unit that stores location wireless quality base station information recorded in association with the wireless communication quality at the location and the base station identification information that identifies the base station that provides the wireless communication connection at the location. And, based on the position radio quality base station information stored in the position radio quality base station information storage unit, the candidate of the route is evaluated as low if the radio communication quality at the position on the route is poor. A cost calculation unit that weights to, a route search unit that searches for the route based on the weighting from the weighted route candidates, and a position stored in the position radio quality base station information storage unit. Radio quality Comparison between the old and new wireless quality comparison units and the old and new wireless quality comparison units that compare the wireless communication quality of the base station information with the wireless communication quality at the timing when the moving object moves toward the destination. Based on the result, the radio quality deterioration amount correction unit that corrects the wireless communication quality deterioration amount for the wireless communication quality of the position radio quality base station information stored in the position radio quality base station information storage unit, and It is a navigation device provided with.
(2) In one aspect of the present invention, when the route search unit may disconnect the wireless communication in the route of the previous search result as a result of the correction of the amount of deterioration of the wireless communication quality, the route of the said route. The navigation device according to (1) above, which performs re-search.
(3) In one aspect of the present invention, the wireless quality deterioration amount correction unit connects the mobile body to wireless communication at a position where it is determined that the wireless communication quality has deteriorated as a result of comparison between the old and new wireless quality comparison units. The navigation device according to any one of (1) and (2) above, which corrects the amount of deterioration in wireless communication quality only in the wireless communication connection range provided by the base station.
(4) In one aspect of the present invention, the wireless quality deterioration amount correction unit corrects the wireless communication quality deterioration amount when the wireless communication quality deterioration amount continuously exceeds a certain value for a certain period of time. It is a navigation device according to any one of 1) to (3).
(5) In one aspect of the present invention, the radio quality deterioration amount correction unit has at least one of a radio frequency band, a radio environment classification, and a distance from a radio communication quality measurement point and a worst value point to a base station. The navigation device according to any one of (1) to (4) above, which changes the correction amount of the wireless communication quality deterioration amount based on any of the above.
(6) In one aspect of the present invention, the position radio quality base station information storage unit is worse than the threshold value at which it is determined that the wireless communication quality is disconnected as a result of the correction of the wireless communication quality deterioration amount. The navigation device according to any one of (1) to (5) above, which stores the base station identification information of another base station and the position radio quality base station information changed to the radio communication quality for the changed position. ..
(7) One aspect of the present invention is the navigation according to any one of (1) to (6) above, wherein the moving body is a moving body for delivery, and the route is a route delivered by the moving body. It is a device.

(8) One aspect of the present invention is a navigation method that provides route information indicating a route from a departure point to a destination to a moving body in which remote monitoring is performed via a wireless communication line, and is a position and a position. The location wireless quality base station information recorded in association with the wireless communication quality at the location and the base station identification information that identifies the base station that provides the wireless communication connection at the location is stored in the location wireless quality base station information storage unit. Based on the position radio quality base station information storage step to be performed and the position radio quality base station information stored in the position radio quality base station information storage unit, wireless communication at a position on the route is performed with respect to the route candidate. A cost calculation step for weighting so that the quality is poor, a route search step for searching the route based on the weighting from the weighted route candidates, and the location radio quality base station. Radio quality old and new comparison step for comparing the wireless communication quality of the position wireless quality base station information stored in the information storage unit with the wireless communication quality at the timing when the moving object moves toward the destination. Based on the comparison result of the old and new wireless quality comparison steps, the wireless communication quality deterioration amount is corrected for the wireless communication quality of the positional wireless quality base station information stored in the positional wireless quality base station information storage unit. It is a navigation method including a radio quality deterioration amount correction step to be performed.

(9) One aspect of the present invention is to a computer of a navigation device that provides route information indicating a route from a departure point to a destination for a moving body in which remote monitoring is performed via a wireless communication line. , The location radio quality base station information recorded in association with the radio communication quality at the location and the base station identification information that identifies the base station that provides the wireless communication connection at the location is stored in the location radio quality base station information storage unit. Based on the position radio quality base station information storage step to be stored and the position radio quality base station information stored in the position radio quality base station information storage unit, the radio at the position on the route is used with respect to the route candidate. A cost calculation step for weighting so that a poor communication quality is evaluated poorly, a route search step for searching the route based on the weighting from the weighted route candidates, and the location radio quality base. Radio quality old and new comparison step for comparing the wireless communication quality of the position wireless quality base station information stored in the station information storage unit with the wireless communication quality at the timing when the moving body moves toward the destination. And, based on the comparison result of the wireless quality old and new comparison step, the wireless communication quality deterioration amount is corrected for the wireless communication quality of the positional wireless quality base station information stored in the positional wireless quality base station information storage unit. It is a computer program for executing the wireless quality deterioration amount correction step.

According to the present invention, it is possible to obtain an effect that stable wireless communication can be realized when a mobile body is remotely monitored by wireless communication.

It is a block diagram which shows the structural example of the navigation system 10 which concerns on one Embodiment. It is a figure which shows the structural example of the position, the radio quality, and the base station ID storage part 403 which concerns on one Embodiment. It is a flowchart which shows the example of the procedure of the route search method which concerns on one Embodiment. It is explanatory drawing for demonstrating an example of the route search method which concerns on one Embodiment. It is explanatory drawing for demonstrating the route search method which concerns on one Embodiment. It is explanatory drawing for demonstrating the effect which concerns on one Embodiment. It is a flowchart which shows the example of the procedure of the navigation method which concerns on one Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a navigation system in a delivery service system that delivers using an autonomously moving robot (hereinafter referred to as a mobile robot) will be described as an example.

FIG. 1 is a block diagram showing a configuration example of the navigation system 10 according to the embodiment. In FIG. 1, the mobile robot 2 communicates with the navigation device 4 via a wireless communication line. The mobile robot 2 is an example of a moving body. The navigation device 4 provides the mobile robot 2 with route information indicating a route from the starting point to the destination.

The navigation device 4 according to the present embodiment further includes a remote monitoring function in addition to the navigation function. The remote monitoring function may be provided by a device other than the navigation device 4 outside the mobile robot 2.

The navigation device 4 remotely monitors the mobile robot 2 by wireless communication by the remote monitoring function. For example, the navigation device 4 receives an image captured by the mobile robot 2 and a sound to be picked up from the mobile robot 2 via a wireless communication line, and displays and reproduces the received image and sound. By viewing the image and the sound, the observer monitors the movement status of the mobile robot 2 in real time. Therefore, in the delivery service system according to the present embodiment, it is required to realize stable wireless communication in the mobile robot 2. Therefore, in the present embodiment, the navigation device 4 provides the route information for realizing stable wireless communication in the mobile robot 2.

Further, in the unlikely event that the wireless communication in the mobile robot 2 becomes unstable and the communication with the navigation device 4 is interrupted, the mobile robot 2 autonomously returns to the place where the communication with the navigation device 4 is restored. It has become. However, such a situation is not desirable. Therefore, it would be better if the route of the mobile robot 2 could be changed to a route where stable wireless communication can be obtained before the wireless communication in the mobile robot 2 becomes unstable and the communication with the navigation device 4 is interrupted. preferable. Therefore, in the present embodiment, the navigation device 4 attempts to change such a route.

Hereinafter, the configuration of the navigation system 10 according to the present embodiment will be described with reference to FIG.

[User terminal]
The user terminal 1 is a terminal used by a user of the delivery service system according to the present embodiment (hereinafter referred to as a delivery service user). The delivery service user requests delivery by designating the destination to which the package is delivered. The user terminal 1 may be a mobile communication terminal device such as a smartphone or a tablet-type computer (tablet PC), or may be a stationary communication terminal device (for example, a stationary personal computer or the like). good.

The user terminal 1 includes a product ordering unit 101 and a destination information input unit 102. The product ordering unit 101 selects products and orders selected products according to operations by the delivery service user.

The product ordering unit 101 manages the remaining amount of the goods owned by the delivery service user in real time, and automatically replenishes the goods when the remaining amount of the goods becomes equal to or less than a preset threshold value. You may place an order.

When the product ordering unit 101 orders a product, the destination information input unit 102 inputs destination information indicating the destination such as an address. The destination information may be specified by the delivery service user each time, or the destination information input unit 102 records the destination information specified by the delivery service user in the past and records the destination information in the record. It may be reused automatically.

Further, the destination information input unit 102 may use the current position acquired by GPS as the destination by using the positioning function by the GPS (Global Positioning System) provided in the user terminal 1. Further, the destination information input unit 102 may add an image of the scenery around the user terminal 1 taken by the camera of the user terminal 1 to the destination information as reference information of the destination.

[Mobile robot]
The mobile robot 2 is a robot capable of autonomous traveling. The mobile robot 2 travels in the city, for example, and delivers the package to the destination designated by the delivery service user.

The mobile robot 2 includes a current position acquisition unit 201, a wireless quality acquisition unit 202, a base station identification information (base station ID) acquisition unit 203, a state acquisition unit 204, a wireless communication unit 205, and a route information storage unit 206. The image pickup unit 207, the operation determination unit 208, and the operation control unit 209 are provided.

The current position acquisition unit 201 acquires the current position (position information) by a positioning system such as GPS. The wireless quality acquisition unit 202 is the wireless communication quality (wireless communication quality information) when the wireless communication unit 205 performs wireless communication with the navigation device 4 for each wireless communication method and wireless frequency band supported by the wireless communication unit 205. ).

The base station ID acquisition unit 203 acquires the base station ID of each base station to which the mobile robot 2 (wireless communication unit 205) can make a wireless communication connection. The base station ID is identification information for individually identifying each base station. Examples of the base station ID include what is called a CID (Cell ID). By combining MCC (Mobile Country Code), MNC (Mobile Network Code), LAC (Location Area Code), and CID (Cell ID: base station ID), each country can be used. The base station of the telecommunications carrier can be uniquely identified.

The state acquisition unit 204 acquires state data (state information) such as the remaining battery level, temperature, and moving speed from various sensors provided in the mobile robot 2.

The wireless communication unit 205 performs wireless communication with the navigation device 4. The wireless communication unit 205 supports wireless communication systems such as LTE (Long Term Evolution) and 5G (fifth generation mobile communication system), and performs wireless communication via a base station of the wireless communication system that it supports. Further, the wireless communication unit 205 corresponds to an unlicensed wireless communication system such as Wi-Fi (registered trademark), and wireless communication may be performed by the unlicensed wireless communication system.

The wireless communication unit 205 transmits the information obtained by the current position acquisition unit 201, the wireless quality acquisition unit 202, the base station ID acquisition unit 203, and the state acquisition unit 204 to the operation monitoring unit 401 of the navigation device 4. Further, the wireless communication unit 205 receives the route information transmitted from the route distribution unit 412 of the navigation device 4 and stores it in the route information storage unit 206. The route information stored in the route information storage unit 206 is utilized for determining the operation of the mobile robot 2.

The image pickup unit 207 images the traveling direction of the mobile robot 2. The motion determination unit 208 determines the next motion of the mobile robot 2. The operation determination unit 208 uses the current position acquired by the current position acquisition unit 201, the captured image captured by the image pickup unit 207, and the like when moving the route indicated by the route information stored in the route information storage unit 206. Then, the operation according to the surrounding environment of the mobile robot 2 is determined.

The motion control unit 209 causes the mobile robot 2 to execute the motion determined by the motion determination unit 208. The motion control unit 209 controls a travel type such as forward movement, retreat, right / left turn, and travel speed of the mobile robot 2, and an operation type other than travel such as a change in the image pickup direction of the image pickup unit 207.

[Mobile terminal]
The mobile terminal 3 is a mobile communication terminal device such as a smartphone or a tablet PC. The mobile terminal 3 may be used as the user terminal 1 or may be separate from the user terminal 1. As the mobile terminal 3, for example, the mobile terminals of all the subscribers who have agreed to acquire the location information with the wireless communication carrier by the subscribers who have subscribed to the specific wireless communication carrier may be targeted.

The mobile terminal 3 periodically reports the current position (position information) and the wireless communication quality (wireless communication quality information) at the current position to the navigation device 4 for each wireless communication method and radio frequency band supported by the mobile terminal 3. ..

[Navigation device]
The navigation device 4 navigates one or more mobile robots 2 from the starting point to the destination. Further, the navigation device 4 performs operation monitoring for one or a plurality of mobile robots 2.

The navigation device 4 includes an operation monitoring unit 401, an operation information storage unit 402, a position / radio quality / base station ID storage unit 403, a map information storage unit 404, a radio quality movement cost conversion unit 405, and a mobile terminal position. Information storage unit 406, outdoor population density estimation unit 407, movement cost calculation unit 408, order information storage unit 409, destination acquisition unit 410, route search unit 411, route distribution unit 412, wireless quality old and new. A comparison unit 413, a radio quality deterioration amount correction unit 414, and another route search instruction unit 415 are provided. In the present embodiment, the wireless quality mobile cost conversion unit 405 and the mobile cost calculation unit 408 correspond to the cost calculation unit.

Each function of the navigation device 4 is realized by the navigation device 4 having computer hardware such as a CPU (Central Processing Unit) and a memory, and the CPU executing a computer program stored in the memory. .. The navigation device 4 may be configured by using a general-purpose computer device, or may be configured as a dedicated hardware device. For example, the navigation device 4 may be configured using a server computer connected to a communication network such as the Internet. Further, each function of the navigation device 4 may be realized by cloud computing. Further, the navigation device 4 may be realized by a single computer, or may be realized by distributing the functions of the navigation device 4 to a plurality of computers. Further, the navigation device 4 may be configured to open a website by using, for example, a WWW system or the like.

The operation monitoring unit 401 performs operation monitoring for one or a plurality of mobile robots 2. The operation monitoring unit 401 performs operation monitoring by associating the position information, wireless communication quality information, and state information received from the mobile robot 2 in real time with the information for identifying the individual of the mobile robot 2 (mobile robot ID). The operation monitoring unit 401 periodically monitors the operation based on information (position information, wireless communication quality information, status information) that is updated periodically, for example, at 1-second intervals. The operation monitoring unit 401 analyzes the position information, wireless communication quality information, and status information received from the mobile robot 2, and when a failure of the mobile robot 2 is detected, for example, issues an alarm to the observer. The operation information storage unit 402 stores information (position information, wireless communication quality information, status information) received from the mobile robot 2 by the operation monitoring unit 401 for investigating the cause when a failure occurs and examining future countermeasures.

The position / radio quality / base station ID storage unit 403 stores the position / radio quality base station information recorded in association with the position information, the radio communication quality information, and the base station ID for each radio communication method and radio frequency band. ..

The position information, the radio communication quality information, and the base station ID recorded in the position radio quality base station information are information transmitted from the mobile robot 2 or the mobile terminal 3 to the navigation device 4. The position information, the radio communication quality information, and the base station ID measured by a device other than the mobile robot 2 and the mobile terminal 3 may be recorded in the position radio quality base station information.

Further, the position information is, for example, GPS coordinates. For indoor facilities and the like that cannot acquire GPS coordinates, absolute position information acquired by an indoor positioning technique such as IMES (Indoor MEssaging System) may be used for position information. Further, the wireless communication quality information is, for example, RSRP (Reference Signal Received Power) indicating the received power of LTE.

The location radio quality base station information may be provided for each date, day of the week, time zone, or event. For example, the location radio quality base station information on weekdays (Monday to Friday) and the location radio quality base station information on holidays (Saturday, Sunday, and holidays) may be provided respectively. For example, the position radio quality base station information in the daytime time zone and the position radio quality base station information in the night time zone may be provided respectively. For example, location radio quality base station information during the New Year, Golden Week, and Obon periods may be provided.

FIG. 2 is a diagram showing a configuration example of the position / radio quality / base station ID storage unit 403 according to the present embodiment. In the example of FIG. 2, the position / radio quality / base station ID storage unit 403 determines the position radio quality base station information 4031 of the radio frequency band _LTE_a and the position radio quality base station of the radio frequency band _LTE_b for the radio communication method "LTE". Information 4032 and the like are stored. Further, the position / radio quality / base station ID storage unit 403 provides the position radio quality base station information 4033 in the radio frequency band _5G_a, the position radio quality base station information 4034 in the radio frequency band _5G_b, etc. for the radio communication method "5G". It is stored.

For example, Band 1 (2.1 GHz), Band 18 (800 MHz), or the like is used as the LTE radio frequency band. Further, as a 5G radio frequency band, for example, a 28GHz band or the like is used.

For example, the position radio quality base station information 4031 is information recorded in association with the radio communication quality and the base station ID in each position_a, position_b, ... Of the radio frequency band_LTE_a of the radio communication method "LTE". .. For example, the position radio quality base station information 4033 is information recorded in association with the radio communication quality and the base station ID at each position_a, position_b, ... Of the radio frequency band _5G_a of the radio communication method "5G". ..

Further, the position radio quality base station information 4032 is information recorded in association with the radio communication quality and the base station ID in each position_a, position_b, ... Of the radio frequency band_LTE_b of the radio communication method "LTE". .. In the position radio quality base station information 4032, the same base station ID_LTE_b_ab is recorded in association with the position_a and the position_b. This is because in the radio frequency band _LTE_b of the wireless communication system "LTE", the base station of the base station ID_LTE_b_ab provided the wireless communication connection at the position _a and the position _b at the time of measuring the wireless communication quality at the position _a and the position _b. Is.

In the location radio quality base station information, the base station ID is information that identifies the base station that provides the wireless communication connection at the location associated with the base station ID. Further, in the location radio quality base station information, the base station ID identifies the base station that provided the radio communication connection at the location at the time of measuring the radio communication quality at the location associated with the base station ID. Information.

In the location radio quality base station information, the radio communication quality and the base station ID recorded in association with the location may be the base station ID of the base station from which the best radio communication quality was obtained at the location. Furthermore, in the location radio quality base station information, the radio communication quality and the base station ID recorded in association with the location are the base station IDs of all the base stations for which the radio communication quality was obtained at the location and the radio communication quality thereof. May be.

In the present embodiment, the location / radio quality / base station ID storage unit 403 stores the location / radio quality base station information of at least the area including the service target area of the delivery service system. The service target area of this delivery service system is a target area (target area) to which the navigation device 4 provides route information. The location / wireless quality / base station ID storage unit 403 according to this embodiment is a wireless communication system (LTE, 5G, etc.) and a wireless frequency for which a wireless communication service is provided in a target area where the navigation device 4 provides route information. For each band (radio frequency band_LTE_a, radio frequency band_LTE_b, radio frequency band_5G_a, radio frequency band_5G_b, etc.), the position included in the target area is recorded in association with the radio communication quality and base station ID at the position. Stores location radio quality base station information.

The map information storage unit 404 stores road map data nationwide and facility data such as various facilities and stores associated therewith. The road map data is given as link data in which, for example, a road on a map is divided into a plurality of parts with an intersection or the like as a node, and the part between each node is defined as a link. This link data includes data such as a unique identifier (link ID), link length, position information (longitude, latitude), angle (direction) data of the start point / end point (node) of the link, road width, road type, and the like. Consists of. The road map data may include lane information indicating a lane through which the mobile robot 2 can pass. Further, the map information storage unit 404 may further store indoor map data.

The wireless quality mobile cost conversion unit 405 is based on the wireless communication method and each position wireless quality base station information stored in the position / wireless quality / base station ID storage unit 403 for each wireless communication method and wireless frequency band, and the wireless communication method and wireless. For each frequency band, the radio communication quality information recorded in association with the location information corresponding to each road is converted into a radio quality link cost.

The wireless quality mobile cost conversion unit 405 executes the wireless quality link cost conversion process for converting the wireless communication quality information into the wireless quality link cost at a predetermined timing. For example, the radio quality mobile cost conversion unit 405 periodically executes the radio quality link cost conversion process. For example, when the location radio quality base station information is added or changed in the location / radio quality / base station ID storage unit 403, the radio quality mobile cost conversion unit 405 has a radio quality link cost for the location radio quality base station information. Execute the conversion process.

The radio quality link cost obtained by the radio quality movement cost conversion unit 405 is stored in the map information storage unit 404 in association with the corresponding link data in the road map data of the map information storage unit 404.

The wireless quality mobile cost conversion unit 405 divides the value of the wireless quality link cost into three stages, for example, and if the wireless communication quality is sufficiently good, the wireless quality link cost is "0", and the wireless communication is not disconnected. However, if the wireless communication quality is poor, the wireless quality link cost is "large", and if the wireless communication may be disconnected, the wireless quality link cost is "∞".

If the wireless communication quality is better than a certain level, the possibility that the wireless communication will be disconnected is sufficiently low. From this, if the predetermined wireless communication quality that can be judged to be sufficiently unlikely to be disconnected is satisfied (for example, if the received power is equal to or higher than the predetermined value), the wireless quality link cost. (For example, the radio quality link cost is “0”), and if not, the radio quality link cost may be increased (for example, the radio quality link cost is “large” or “∞”).

The wireless quality mobile cost conversion unit 405, for example, selects a value near the minimum value of the wireless communication quality information in consideration of the minimum value or the deviation value of the wireless communication quality information from the wireless communication quality information group corresponding to each link data. It may be subject to conversion of radio quality link costs. This is because the possibility that the wireless communication is disconnected when the mobile robot 2 travels on the road of the link data is calculated as a risk.

The route search unit 411, which will be described later, sequentially calculates (integrates) the cost of the road (link) from the departure point to the destination to the next reachable intersection (node), and then from the departure point to the destination. Select the route with the lowest cost to the ground. Therefore, setting a small radio quality link cost value for a road makes it easier for the road to be selected as a route.

The mobile terminal position information storage unit 406 stores the history of the position information of each mobile terminal 3. For example, the GPS coordinates of each mobile terminal 3 are stored in association with the time.

The outdoor population density estimation unit 407 determines whether each mobile terminal 3 is indoors or outdoors based on the history of the position information stored in the mobile terminal position information storage unit 406, and based on this determination result. Based on this, the outdoor population density is estimated for each preset area. The outdoor population density is the number of people per unit area of people who are outdoors. The outdoor population density obtained by the outdoor population density estimation unit 407 is stored in the map information storage unit 404 in association with the corresponding link data in the road map data of the map information storage unit 404.

For example, when it is determined that the change in the position information of a certain mobile terminal 3 is less than a certain value and there is almost no change, the outdoor population density estimation unit 407 determines that the mobile terminal 3 is indoors, and the change in the position information is changed. If it is judged that the value is above a certain level and has changed to some extent, it is judged that the user was outdoors.

Further, the outdoor population density estimation unit 407 compares the position information of each mobile terminal 3 with the road map data stored in the map information storage unit 404 to perform map matching, and the mobile terminal 3 uses the road. It may be presumed that it was done. The map matching is a process of correcting the position information obtained by GPS, which may contain an error, so as to be on the road by using the map information. Map matching is used, for example, in car navigation systems.

Further, the outdoor population density estimation unit 407 may determine whether the moving means of the mobile terminal 3 is walking or a vehicle based on the moving speed of the mobile terminal 3.

The outdoor population density estimation unit 407 may estimate each outdoor population density for each month, day of the week, or time zone. This is because even in the same area, the outdoor population density may change significantly depending on the month, day of the week, time zone, and the like.

Further, the outdoor population density estimation unit 407 may estimate the outdoor population density by a method different from the method using the position information of the mobile terminal 3. For example, the outdoor population density estimation unit 407 may use the image captured by the mobile robot 2 and estimate the outdoor population density based on the image recognition result of a person for the captured image.

The travel cost calculation unit 408 periodically calculates the total link cost for each link of each road by using the information stored in the map information storage unit 404 for each wireless communication method and wireless frequency band. do. The travel cost calculation unit 408 calculates the total link cost using at least the radio quality link cost. The total link cost obtained by the movement cost calculation unit 408 is stored in the map information storage unit 404 in association with the corresponding link data in the road map data of the map information storage unit 404.

The travel cost calculation unit 408 weights each link on each road based on the radio quality link cost so that a poor wireless communication quality is evaluated as low. For example, the travel cost calculation unit 408 weights the links on the road where it is determined that the wireless communication is likely to be disconnected based on the radio quality link cost so that the total link cost is the largest. You may. As a result, stable wireless communication in the mobile robot 2 is realized.

Further, the movement cost calculation unit 408 may calculate the total link cost based on the outdoor population density. The travel cost calculation unit 408 may weight the links on the road whose outdoor population density is equal to or higher than the threshold value so that the total link cost becomes large. As a result, the mobile robot 2 aims to travel on a road with few people.

Further, the movement cost calculation unit 408 may calculate the total link cost based on at least one of the type of the mobile robot 2 and the contents of the delivery by the mobile robot 2 and the road condition of each link of each road. good. The types of the mobile robot 2 are classified according to the size, structure, and the like of the mobile robot 2. Further, the types of the mobile robot 2 are classified according to the wireless communication method and the wireless frequency band that can be used by the mobile robot 2. The contents of the delivery by the mobile robot 2 are, for example, the type of the package to be delivered by the mobile robot 2, the estimated load amount, and the like.

For example, the movement cost calculation unit 408 can safely travel on a link of a road having a road width less than the threshold value in the case of the small mobile robot 2, so that the total link cost is not increased, but the large mobile robot. In the case of 2, the total link cost is increased. Further, since it is assumed that it may be difficult for the moving cost calculation unit 408 to get over the step on the road depending on the structure of the mobile robot 2, the link of the road having the step is provided to the mobile robot 2 of the corresponding type. On the other hand, the total link cost is increased. Further, when the type of the package delivered by the mobile robot 2 is a fragile item, the movement cost calculation unit 408 preferably travels on a road with less unevenness, so that the total link cost of the link on the road with less unevenness is reduced. On the other hand, the total link cost of links on roads with many irregularities will be increased.

Further, the movement cost calculation unit 408 may use an evaluation element used in a known navigation system as information used for calculating the total link cost. The evaluation elements used in the known navigation system are, for example, the required distance of the link, the required time for movement, the weighting based on the road condition and the road width, the weighting based on the signal frequency, the weighting based on the congestion tendency, and the like.

The order information storage unit 409 receives the order information of the product order from the user terminal 1 and stores the received order information. The order information storage unit 409 performs a purchase process in cooperation with a purchase system (not shown) and formulates a product delivery plan. The order information storage unit 409 stores scheduled delivery information such as a departure place, a destination, and a time zone in which the mobile robot 2 delivers a product according to the formulated product delivery plan. The destination acquisition unit 410 acquires destination information from the order information or scheduled delivery information stored in the order information storage unit 409.

The route search unit 411 searches for a route from the departure point of the mobile robot 2 to the destination as a route to be traveled by the mobile robot 2 based on the total link cost calculated by the movement cost calculation unit 408. The destination of the mobile robot 2 is a place indicated by the destination information acquired by the destination acquisition unit 410. The departure point of the mobile robot 2 is set in advance. For example, a delivery base for goods (for example, a distribution warehouse in which goods are stored, a delivery handling store closest to the destination, etc.) is preset as a departure point for the mobile robot 2. When the mobile robot 2 is transported to the vicinity of the destination by the vehicle, the destination location of the mobile robot 2 is preset as the departure point of the mobile robot 2.

As the route search method used by the route search unit 411, for example, the Dijkstra method, the A * algorithm, the genetic algorithm, or the like can be used.

The route distribution unit 412 transmits the route information indicating the route as a result of the search by the route search unit 411 to the mobile robot 2.

Here, a route search method according to the present embodiment will be described with reference to FIG. FIG. 3 is a flowchart showing an example of the procedure of the route search method according to the present embodiment.

(Step S1) The route search unit 411 acquires a starting point where the mobile robot 2 starts traveling and a destination which is the destination where the mobile robot 2 travels.

(Step S2) The route search unit 411 acquires the type of the mobile robot 2 and the contents of the delivery.

(Step S3) The route search unit 411 recognizes the wireless communication method and radio frequency band that can be used by the mobile robot 2 from the type of the mobile robot 2 acquired in step S2. The correspondence between the type of the mobile robot 2 and the available wireless communication method and wireless frequency band is set in advance in the navigation device 4.

(Step S4) The route search unit 411 designates the search range including the departure point and the destination of the mobile robot 2 acquired in step S1 and the link cost calculation condition to the movement cost calculation unit 408, and performs the search. Instruct to calculate the total link cost for each link on each road within range. The link cost calculation conditions include the type of the mobile robot 2 and the contents of delivery. The link cost calculation condition includes at least information indicating an available wireless communication method and wireless frequency band of the mobile robot 2.

The travel cost calculation unit 408 calculates the total link cost for each link of each road within the search range for each radio communication method and radio frequency band in response to the total link cost calculation instruction from the route search unit 411. .. In this calculation of the total link cost, weighting is performed for each link of each road so that a poor wireless communication quality is evaluated as low. The movement cost calculation unit 408 stores the total link cost of the calculation result in the map information storage unit 404 in association with the corresponding link data in the road map data of the map information storage unit 404. When the mobile robot 2 has a plurality of wireless communication methods and radio frequency bands that can be used by the mobile cost calculation unit 408, the mobile cost calculation unit 408 can obtain the best wireless communication quality for each link on each road. The total link cost for the method and the radio frequency band may be stored in the map information storage unit 404 in association with the corresponding link data.

The movement cost calculation unit 408 responds to the route search unit 411 that the calculation of the total link cost is completed.

(Step S5) The route search unit 411 refers to the departure point and the destination of the mobile robot 2 acquired in step S1 from the departure point to the destination based on the total link cost calculated by the movement cost calculation unit 408 in step S4. Search for a route to reach the ground. In this route search, a route that minimizes the total total link cost of each link from the starting point to the destination is searched.

(Step S6) The route distribution unit 412 transmits the route information indicating the route of the search result in step S5 to the mobile robot 2.

FIG. 4 is an explanatory diagram for explaining an example of the route search method. FIG. 5 is an explanatory diagram for explaining the route search method according to the present embodiment. In FIGS. 4 and 5, circles indicate nodes, and lines connecting the nodes indicate links. Further, the node of the departure place is S, and the node of the destination is G. In addition, the number written on the link indicates the link cost. FIG. 4 shows the link cost when the wireless communication quality is not taken into consideration. On the other hand, FIG. 5 shows the total link cost according to the present embodiment when the wireless communication quality is taken into consideration. Further, here, it is assumed that the link L2 has poor wireless communication quality and there is a high possibility that the wireless communication will be disconnected.

In the case of the link cost in FIG. 4, as a result of the route search, as a route from the departure point "node S" to the destination "node G", the route that minimizes the total link cost is "L1 → L2 → L3". Is selected. Since the wireless communication quality is not taken into consideration in the link cost of FIG. 4, the link L2, which is likely to be disconnected from the wireless communication, is selected as the route. As a result, if the wireless communication between the mobile robot 2 and the navigation device 4 is cut off in the selected route, the mobile robot 2 may not be able to be remotely monitored.

On the other hand, in FIG. 5, the total link cost “4 + ∞” is set for the link L2, in which the radio quality link cost “∞” is added to the link cost “4” in FIG. As a result, according to the total link cost of FIG. 5, the link L2, which is likely to be disconnected from the wireless communication, is not selected as the route. Then, in the case of the link cost of FIG. 5, as a result of the route search, as a route from the departure place "node S" to the destination "node G", the total link cost is minimized "L4 → L5". Is selected. According to this selected route "L4 → L5", stable wireless communication in the mobile robot 2 can be realized. As a result, the mobile robot 2 can be stably monitored remotely by wireless communication.

The explanation is returned to FIG.
The old and new comparison unit 413 has the current wireless communication quality at the current position of the mobile robot 2 monitored by the operation monitoring unit 401, and the position / wireless quality / position radio quality stored in the base station ID storage unit 403. Compare the radio communication quality of the position corresponding to the current position of the base station information. The timing of this comparison is the timing at which the mobile robot 2 moves toward the destination. The timing at which the mobile robot 2 moves toward the destination is the timing at which the mobile robot 2 starts delivery, the timing at which the mobile robot 2 is moving for delivery, and the like. That is, the radio quality old / new comparison unit 413 has the past radio communication quality recorded in the position radio quality base station information in the area where the mobile robot 2 delivers, and the radio at the timing when the mobile robot 2 actually delivers. Compare with communication quality. This makes it possible to determine whether or not the wireless communication quality at the timing when the mobile robot 2 actually delivers is deteriorated with respect to the past wireless communication quality.

The radio quality deterioration amount correction unit 414 determines the wireless communication quality of the position radio quality base station information stored in the position / radio quality / base station ID storage unit 403 based on the comparison result of the radio quality old / new comparison unit 413. Then, the amount of deterioration in wireless communication quality is corrected. The wireless communication quality deterioration amount is an amount in which the wireless communication quality at the timing when the mobile robot 2 actually delivers is deteriorated from the past wireless communication quality recorded in the position wireless quality base station information.

The wireless quality deterioration amount correction unit 414 executes the wireless communication quality deterioration amount correction process when it is determined that the wireless communication quality has deteriorated as a result of comparison by the wireless quality old / new comparison unit 413. For example, the wireless quality deterioration amount correction unit 414 performs wireless communication quality deterioration amount correction processing when the wireless communication quality deterioration amount exceeds a certain value continuously for a certain period as a result of comparison by the wireless quality old and new comparison units 413. May be executed.

The target for executing the wireless communication quality deterioration amount correction process will be described. As a result of comparison by the old and new wireless quality comparison unit 413, the position where it is determined that the amount of deterioration in wireless communication quality has deteriorated is referred to as a deterioration position. The deterioration position is, for example, a position where the amount of deterioration in wireless communication quality continuously exceeds a certain value for a certain period of time as a result of comparison by the old and new wireless quality comparison units 413.

In the route where the mobile robot 2 moves to the destination, the base station to which the mobile robot 2 is wirelessly connected may perform a handover between a plurality of base stations having different installation locations. At this time, since the installation location of each base station is different, it is conceivable that the deterioration of the wireless communication quality is limited to the area where the wireless communication is connected to the same base station.

Therefore, it is preferable to correct the amount of deterioration in wireless communication quality by limiting the wireless communication connection range provided by the base station to which the mobile robot 2 wirelessly connects in the deteriorated position. Therefore, the radio quality deterioration amount correction unit 414 sets the base station ID associated with the deterioration position as the correction target base station ID in the position radio quality base station information. The radio quality deterioration amount correction unit 414 sets the radio communication quality associated with the correction target base station ID as the correction target radio communication quality in the position radio quality base station information.

The wireless communication quality deterioration amount correction process will be described. Here, RSRP will be described as an example of wireless communication quality.
The radio quality deterioration amount correction unit 414 is corrected when the current RSRP reported from the mobile robot 2 is Rc (dBm) and the RSRP of the position radio quality base station information is Rp (dBm) at the deterioration position. The worst value Rw (dBm) of the RSRP of wireless communication quality is corrected to be updated to "Rw- (Rp-Rc)".

It should be noted that the worst value Rw (dBm) is not simply corrected by using "-(Rp-Rc)" as the correction amount of the wireless communication quality deterioration amount, but the wireless frequency band and the wireless environment classification. , The correction amount of the wireless communication quality deterioration amount may be changed based on at least one of the measurement point of the wireless communication quality and the distance from the worst value point to the base station.

For example, the correction amount of the amount of deterioration in wireless communication quality is changed between the high frequency band with strong straightness such as the 28 GHz band used as the 5 G wireless frequency band and the 800 MHZ band used as the LTE wireless frequency band. You may.

For example, open areas, suburbs, small and medium-sized cities and large cities are set as the wireless environment classification to which the base station installation location belongs, and the correction target base station ID belongs to open areas, suburbs, small and medium-sized cities and large cities. The correction amount of the wireless communication quality deterioration amount may be changed.

For example, in the position radio quality base station information, the distance from the position (measurement point) associated with each correction target radio communication quality to the base station of the correction target base station ID and the base from the worst value position (worst value point). The correction amount of the wireless communication quality deterioration amount may be changed depending on the relationship with the distance to the station (for example, the magnitude ratio, etc.).

Further, machine learning may be used as an example of a method for determining the correction amount of the wireless communication quality deterioration amount. Specifically, when the wireless communication quality actually deteriorates at the measurement point, how the wireless communication quality at the worst value point changes is actually measured. Then, a machine learning model is generated by performing machine learning using the measured data, and the correction amount of the wireless communication quality deterioration amount is determined using the machine learning model.

For the base station ID to be corrected, if the difference between the current wireless communication quality and the past wireless communication quality is larger than a certain level, the correction amount for the amount of deterioration of the wireless communication quality is adjusted, and the correction target wireless communication quality is the wireless communication. The amount may be worse than the threshold value (cutting judgment threshold value) at which cutting occurs. In such a case, the tilt angle of the base station has been changed, and the past record and tendency of the wireless communication quality of the communication area (coverage) of the base station cannot be trusted. This is because the wireless environment may have changed.

Further, the radio quality deterioration amount correction unit 414 determines the base station ID and the radio of the position radio quality base station information with respect to the position where the correction target wireless communication quality becomes worse than the disconnection determination threshold after the correction of the wireless communication quality deterioration amount. The communication quality may be replaced with another base station ID and wireless communication quality. As a result, the wireless quality deterioration amount correction unit 414 determines whether or not the mobile robot 2 can avoid disconnection of wireless communication by connecting to another base station by wireless communication at the position.

In addition, the radio quality deterioration amount correction unit 414 determines the base station ID and the radio of the position radio quality base station information with respect to the position where the correction target wireless communication quality becomes worse than the disconnection determination threshold after the correction of the wireless communication quality deterioration amount. The communication quality may be replaced with another base station ID and wireless communication quality having a wireless communication quality better than the disconnection determination threshold and its base station ID.

The above is the description of the wireless communication quality deterioration amount correction process.

The wireless quality deterioration amount correction unit 414 performs the wireless communication quality deterioration amount correction process for the correction target wireless communication quality of the position radio quality base station information, and then corrects the wireless communication quality deterioration amount of the corrected wireless communication quality. Is determined by the disconnection determination threshold. In this determination, when the corrected wireless communication quality after the correction of the amount of deterioration of the wireless communication quality is worse than the disconnection determination threshold value, it is determined that the wireless communication is disconnected at the position associated with the corrected wireless communication quality. .. On the other hand, when the corrected wireless communication quality after the correction of the amount of deterioration of the wireless communication quality is better than the disconnection determination threshold value, it is determined that the wireless communication disconnection does not occur at the position associated with the corrected wireless communication quality. ..

When it is determined that the wireless communication is disconnected as a result of the correction of the wireless communication quality deterioration amount by the wireless quality deterioration amount correction unit 414, the separate route search instruction unit 415 of each position associated with the correction target base station ID The wireless quality link cost is updated by the wireless quality mobile cost conversion unit 405 to the wireless quality link cost converted from the corrected wireless communication quality after the correction of the amount of deterioration of the wireless communication quality. Next, another route search instruction unit 415 instructs the route search unit 411 to re-search the route using the updated radio quality link cost.

The route search unit 411 searches for a route to the destination of the mobile robot 2 again in response to an instruction for re-searching the route from another route search instruction unit 415. At the time of re-searching for this route, if the mobile robot 2 is before the departure for delivery, the route from the departure point of delivery to the destination is searched for. On the other hand, when the mobile robot 2 is already moving for delivery at the time of re-searching the route, the route from the current position of the mobile robot 2 to the destination is searched. The route search method in the route re-search is the same as the above-mentioned method.

The route distribution unit 412 transmits the route information indicating the route as a result of the re-search by the route search unit 411 to the mobile robot 2, and moves so as to update the route information held by the mobile robot 2 to the route information of the re-search result. Instruct robot 2. The mobile robot 2 receives the route information of the re-search result transmitted from the route distribution unit 412 of the navigation device 4, and updates the route information in the route information storage unit 206 with the route information of the re-search result.

In the present embodiment, the navigation device 4 predicts in advance whether or not the wireless communication disconnection will occur in the route on which the mobile robot 2 will move in the future, and if it is predicted that the wireless communication disconnection will occur, another route is used. Explore. As a result, it is possible to prevent the situation in which the mobile robot 2 turns back the route after the wireless communication is disconnected.

FIG. 6 is an explanatory diagram for explaining the effect according to the present embodiment. In FIG. 6, C1 and C1a are communication areas of the base station B1. The communication area C1 is a communication area recorded in the position radio quality base station information at the time of the first route search of the mobile robot 2. On the other hand, the communication area C1a is a communication area at the timing when the mobile robot 2 actually moves toward the destination G. C2 is a communication area of base station B2. The communication area C2 is the same at the time of the first route search of the mobile robot 2 and at the timing when the mobile robot 2 actually moves toward the destination G.

As a result of the first route search of the mobile robot 2, a route consisting of a route R1 (indicated by a solid line in the figure) and a route R2 (indicated by a broken line in the figure) is a route from the starting point S to the destination G. It is determined. The path R1 is a portion where the mobile robot 2 connects to the base station B1 by wireless communication. The path R2 is a portion where the mobile robot 2 connects to the base station B2 by wireless communication.

At the time of the first route search of the mobile robot 2, the route R1 and the route R2 exist in the communication areas C1 and C2 of the base stations B1 and B2 in the position radio quality base station information, so that the mobile robot 2 has a route from the departure point S. It was predicted that the wireless communication would not be disconnected even if the user moved to the destination G via the route R1 and the route R2. However, at the timing when the mobile robot 2 actually moves toward the destination G, the communication area of the base station B1 is reduced from the communication area C1 to the communication area C1a, so that the partial R1b of the route R1 communicates. It is out of the range of area C1a. Therefore, when the mobile robot 2 moves on the route R1, a situation may occur in which the mobile robot 2 turns back on the route R1 due to a disconnection of wireless communication in the portion R1b of the route R1.

According to the present embodiment, at the timing when the mobile robot 2 moves toward the destination G, the route R1 is based on the comparison result between the current wireless communication quality and the past wireless communication quality of the position wireless quality base station information. It is expected that the wireless communication will be disconnected. Then, the route to the destination G of the mobile robot 2 is re-searched based on the current wireless communication quality. As a result of this re-search, another route to the destination G is searched, so that the situation in which the mobile robot 2 returns to the route R1 after the wireless communication is disconnected in the partial R1b of the route R1 can be prevented. Can be done.

Factors that make the current wireless communication quality worse than the past wireless communication quality include the installation of radio wave propagation obstacles such as buildings and the increase in the load on the base station.

The navigation method according to the present embodiment will be described with reference to FIG. 7. FIG. 7 is a flowchart showing an example of the procedure of the navigation method according to the present embodiment.

(Step S101) The old and new wireless quality comparison unit 413 is stored in the current wireless communication quality at the current position of the mobile robot 2 monitored by the operation monitoring unit 401, and the position / wireless quality / base station ID storage unit 403. Location Radio quality Compare with the radio communication quality of the location corresponding to the current location of the base station information.

(Step S102) As a result of the comparison in step S101, it is determined whether or not the wireless communication quality has deteriorated. For example, if the amount of deterioration of wireless communication quality continues for a certain period of time and exceeds a certain value at a certain position, it is determined that the wireless communication quality has deteriorated, and if not, the deterioration is so serious that the wireless communication is disconnected. Therefore, it is judged that the wireless communication quality has not deteriorated. In the case of RSRP as an example of wireless communication quality, the fixed period is, for example, 30 seconds, and the constant value is, for example, −20 dB.

If the wireless communication quality deteriorates as a result of the determination in step S102, the process proceeds to step S103. On the other hand, if the wireless communication quality has not deteriorated, the process of FIG. 7 is terminated.

(Step S103) The radio quality deterioration amount correction unit 414 sets the base station ID associated with the deterioration position as the correction target base station ID in the position radio quality base station information. In the position radio quality base station information, each position associated with the correction target base station ID is information indicating the wireless communication connection range related to the correction target base station ID.

(Step S104) The wireless quality deterioration amount correction unit 414 wirelessly communicates with respect to the correction target wireless communication quality in the wireless communication connection range related to the correction target base station ID extracted in step S103 in the position wireless quality base station information. Executes quality deterioration amount correction processing.

(Step S105) As a result of executing the wireless communication quality deterioration amount correction process in step S104, the wireless quality deterioration amount correction unit 414 disconnects the worst value of the correction target wireless communication quality in the wireless communication connection range related to the correction target base station ID. It is judged whether or not it is worse than the judgment threshold. If the result of this determination is worse than the disconnection determination threshold value, the process proceeds to step S106. On the other hand, if it is not worse than the disconnection determination threshold value, the process of FIG. 7 is terminated.

(Step S106) The radio quality deterioration amount correction unit 414 bases the position radio quality base station information at a position where the correction target wireless communication quality in the wireless communication connection range related to the correction target base station ID is worse than the disconnection determination threshold. Replace the station ID and radio communication quality with another base station ID and radio communication quality. Next, the wireless quality deterioration amount correction unit 414 determines whether or not the mobile robot 2 can avoid disconnection of wireless communication by connecting to the other base station by wireless communication at the position. As a result of this determination, if the disconnection of the wireless communication can be avoided, the process of FIG. 7 is terminated. On the other hand, when the mobile robot 2 cannot make a wireless communication connection with the other base station, or even if the mobile robot 2 makes a wireless communication connection with the other base station, the wireless communication quality is worse than the disconnection determination threshold and the wireless communication is performed. If it is not possible to avoid disconnection of communication, the process proceeds to step S107.

(Step S107) Another route search instruction unit 415 corrects the radio quality link cost of each position associated with the correction target base station ID after the wireless communication quality deterioration amount is corrected by the radio quality movement cost conversion unit 405. Update from communication quality to converted radio quality link cost. Next, another route search instruction unit 415 instructs the route search unit 411 to re-search the route using the updated radio quality link cost. The route search unit 411 searches for a route to the destination of the mobile robot 2 again in response to an instruction for re-searching the route from another route search instruction unit 415.

(Step S108) The route distribution unit 412 transmits the route information indicating the route as a result of the re-search by the route search unit 411 to the mobile robot 2, and the route information held by the mobile robot 2 is the route of the re-search result. Update to information.

The process of FIG. 7 described above may be executed every time the radio communication quality of the position radio quality base station information is updated. This is to detect the possibility of disconnection of wireless communication in the mobile robot 2 at an early stage.

Even in the result of re-searching the route, if the destination cannot be reached from the departure point without passing through the link where the wireless communication is likely to be disconnected, the link is transferred from the departure point to the destination. It may be selected as the route to reach. If there is a link in the path of the search result that is likely to be disconnected from the wireless communication, the route search unit 411 outputs the wireless disconnection alert information indicating the link. The remote monitoring observer can recognize in advance the location where the wireless communication between the mobile robot 2 and the navigation device 4 is likely to be disconnected by the wireless disconnection alert information.

According to the above-described embodiment, it is possible to provide route information for realizing stable wireless communication in the mobile robot 2. Further, before the wireless communication in the mobile robot 2 becomes unstable and the communication with the navigation device 4 is interrupted, the route of the mobile robot 2 can be changed to a route in which stable wireless communication can be obtained. This has the effect that stable wireless communication can be realized when the mobile robot 2 is remotely monitored by wireless communication. Further, it is possible to prevent the situation where the mobile robot 2 turns back the route after the wireless communication is disconnected.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes design changes and the like within a range that does not deviate from the gist of the present invention.

In the above-described embodiment, the navigation system is applied to the delivery service system, but it may be applied to other systems other than the delivery service system. For example, the navigation system according to the above-described embodiment may be applied to a road inspection service system that inspects a road by a mobile robot.

Further, in the above-described embodiment, a mobile robot is taken as an example as a mobile body, but the present invention is not limited to this. As the moving body, a vehicle that automatically drives (automated driving vehicle), an autonomously flying vehicle, or the like may be applied.

Further, a computer program for realizing the functions of the above-mentioned devices may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by the computer system and executed. The "computer system" here may include hardware such as an OS and peripheral devices.
The "computer-readable recording medium" is a flexible disk, a magneto-optical disk, a ROM, a writable non-volatile memory such as a flash memory, a portable medium such as a DVD (Digital Versatile Disc), and a built-in computer system. A storage device such as a hard disk.

Further, the "computer-readable recording medium" is a volatile memory inside a computer system that serves as a server or client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line (for example, DRAM (Dynamic)). It also includes those that hold the program for a certain period of time, such as Random Access Memory)).
Further, the program may be transmitted from a computer system in which this program is stored in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the "transmission medium" for transmitting a program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
Further, the above program may be for realizing a part of the above-mentioned functions. Further, a so-called difference file (difference program) may be used, which can realize the above-mentioned function in combination with a program already recorded in the computer system.

1 ... User terminal, 2 ... Mobile robot, 3 ... Mobile terminal, 4 ... Navigation device, 10 ... Navigation system, 401 ... Operation monitoring unit, 402 ... Operation information storage unit, 403 ... Location / wireless quality / base station ID storage Unit, 404 ... Map information storage unit, 405 ... Wireless quality movement cost conversion unit, 406 ... Mobile terminal location information storage unit, 407 ... Outdoor population density estimation unit, 408 ... Movement cost calculation unit, 409 ... Order information storage unit, 410 ... destination acquisition unit, 411 ... route search unit, 412 ... route distribution unit, 413 ... wireless quality old / new comparison unit, 414 ... wireless quality deterioration amount correction unit, 415 ... different route search instruction unit

Claims (9)

It is a navigation device that provides route information indicating a route from a departure point to a destination for a mobile body in which remote monitoring is performed via a wireless communication line.
Location radio quality base station that stores location radio quality base station information recorded in association with location, radio communication quality at that location, and base station identification information that identifies the base station that provides the radio communication connection at that location. Information storage unit and
Based on the position radio quality base station information stored in the position radio quality base station information storage unit, the route candidates are weighted so that the radio communication quality at the position on the route is poorly evaluated. And the cost calculation unit
A route search unit that searches for the route based on the weighting from the weighted candidates for the route.
The radio communication quality of the position radio quality base station information stored in the position radio quality base station information storage unit is compared with the radio communication quality at the timing when the moving body moves toward the destination. Wireless quality old and new comparison department and
Based on the comparison result of the old and new wireless quality comparison units, the wireless communication quality deterioration amount is corrected for the wireless communication quality of the positional wireless quality base station information stored in the positional wireless quality base station information storage unit. Wireless quality deterioration amount correction unit and
Navigation device with. The route search unit re-searches the route when there is a possibility that the wireless communication may be disconnected in the route of the previous search result as a result of the correction of the amount of deterioration of the wireless communication quality.
The navigation device according to claim 1. The wireless quality deterioration amount correction unit is within the wireless communication connection range provided by the base station to which the mobile is connected to wireless communication at a position where it is determined that the wireless communication quality has deteriorated as a result of comparison between the old and new wireless quality comparison units. The amount of deterioration in wireless communication quality is corrected in a limited manner.
The navigation device according to any one of claims 1 or 2. The wireless quality deterioration amount correction unit corrects the wireless communication quality deterioration amount when the wireless communication quality deterioration amount continuously exceeds a certain value for a certain period of time.
The navigation device according to any one of claims 1 to 3. The radio quality deterioration amount correction unit is based on at least one of the radio frequency band, the radio environment classification, the measurement point of the radio communication quality, and the distance from the worst value point to the base station. Change the amount of deterioration correction amount,
The navigation device according to any one of claims 1 to 4. The position wireless quality base station information storage unit is another base for a position where the wireless communication quality is worse than the threshold value at which the disconnection of the wireless communication is determined as a result of the correction of the wireless communication quality deterioration amount. Stores the base station identification information of the station and the location radio quality base station information changed to the radio communication quality.
The navigation device according to any one of claims 1 to 5. The moving body is a moving body that performs delivery.
The route is a route delivered by the moving object.
The navigation device according to any one of claims 1 to 6. It is a navigation method that provides route information indicating a route from a departure point to a destination for a mobile body in which remote monitoring is performed via a wireless communication line.
Location radio quality base station information stored in association with location, radio communication quality at that location, and base station identification information that identifies the base station that provides the radio communication connection at that location. Location wireless quality base station information storage step to be stored in the unit,
Based on the position radio quality base station information stored in the position radio quality base station information storage unit, the route candidates are weighted so that the radio communication quality at the position on the route is poorly evaluated. And the cost calculation step to do
A route search step for searching for the route based on the weighting from the weighted candidates for the route, and
The radio communication quality of the position radio quality base station information stored in the position radio quality base station information storage unit is compared with the radio communication quality at the timing when the moving body moves toward the destination. Wireless quality old and new comparison steps and
Based on the comparison result of the old and new wireless quality comparison steps, the wireless communication quality deterioration amount is corrected for the wireless communication quality of the positional wireless quality base station information stored in the positional wireless quality base station information storage unit. Wireless quality deterioration amount correction step and
Navigation methods including. To the computer of the navigation device that provides route information indicating the route from the origin to the destination for a mobile body in which remote monitoring is performed via a wireless communication line.
Location radio quality base station information stored in association with location, radio communication quality at that location, and base station identification information that identifies the base station that provides the radio communication connection at that location. Location wireless quality base station information storage step to be stored in the unit,
Based on the position radio quality base station information stored in the position radio quality base station information storage unit, the route candidates are weighted so that the radio communication quality at the position on the route is poorly evaluated. And the cost calculation step to do
A route search step for searching for the route based on the weighting from the weighted candidates for the route, and
The radio communication quality of the position radio quality base station information stored in the position radio quality base station information storage unit is compared with the radio communication quality at the timing when the moving body moves toward the destination. Wireless quality old and new comparison steps and
Based on the comparison result of the old and new wireless quality comparison steps, the wireless communication quality deterioration amount is corrected for the wireless communication quality of the positional wireless quality base station information stored in the positional wireless quality base station information storage unit. Wireless quality deterioration amount correction step and
A computer program to run.

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